This application incorporates by reference Taiwanese application Serial No. 90122165, filed Sep., 6, 2001.
1. Field of the Invention
The invention relates in general to a protective cover applicable to the electronic products, and more particularly to a protective cover with a ternary structure, and the structural flexibility accomplishes the on-off condition of the cover.
2. Description of the Related Art
Today, computer, communication, and consumer (3C) products play a very important role in the global electronic industries. Since the life circle of modern electronic products is short, the trend of the modern product is leading to a handy design, which possesses less weight and good mechanical strength. With the rapid development of 3C products, the future market demands will be extremely massive for the portable products, such as laptop POs, cellular phones, Personal Digital Assistants (PDA), etc. Most electronic products are further equipped with expansion slots that are designed for offering add-ons, such as MP3 players or additional memory storage. However, the conventional protective cover designs for covering the expansion slots have failed to consider the portability of the products.
FIG. 1 is a perspective view of a conventional protective cover for a PDA expansion slot. The PDA 100 has a bottom cover 101 and a protective cover 110. The expansion slot (not shown in FIG. 1) is situated beneath the bottom cover 101, and is designed for inserting an additional memory card, such as a Compact Flash (CF) card. The protective cover 110, which is closed in FIG. 1, is designed for protecting the expansion slot. FIG. 2A is a cross-sectional view of the protective cover of FIG. 1. The protective cover 110 has a fastening portion 211 and a hinge 212. When the protective cover 110 is closed, it attaches firmly to the bottom cover 101 at the fastening portion 211. The hinge 212 is a jointed device that allows the rotating of the protective cover 110 on the bottom cover 101. However, if the user forgets to close the protective cover 110, the additional memory card may be dropped and missing, or the protective cover 110 may be damaged under careless impact. Also, this conventional design of the protective cover 110 does not operate smoothly, and the use of the hinge 212 increases the PDA production cost.
Currently, various protective cover designs are commercially available. FIG. 2B is a cross-sectional view of another conventional protective cover for the expansion slot. The protective cover 210 has a fastening portion 213 and an insertion portion 214. When the protective cover 210 is being closed, the insertion portion 214 is inserted into the recess of the bottom cover 201 and the fastening portion 211 attaches firmly to the bottom cover 201. Accordingly, the protective cover 210 can be attached to the opening of the expansion slot. When the expansion slot is needed, the protective cover 210 is lifted to make the fastening portion 213 and the insertion portion 214 unjoint. However, this design for separating the protective cover 210 and the bottom cover 201 is not very thoughtful. It is very possible for the unwary user to lose the protective cover 210 and need to buy a new one.
A further example of the conventional protective cover for the expansion slot is to weld the protective cover and the bottom cover. FIG. 2C is a cross-sectional view of a further conventional protective cover for the expansion slot. The protective cover 220, which also has a fastening portion 215, is made of a flexible material. Using the welded joint method, the protective cover 220 is connected to the bottom cover 204 by the welding end 216. When the expansion slot is needed, the fastening portion 215 is separated from the bottom cover 204, and the flexible protective cover 220 is then bent to open. In this case, the protective cover 220 is designed as an integrated part of the bottom cover 204 by welding. If the external force applied on the protective cover 220 disappears, the flexibility of the protective cover 220 allows it snap back to its original place. Therefore, these unpleasant situations, such as losing the protective cover and/or forgetting to close the protective cover, can be avoided. However, the material difference between the protective cover 220 and the bottom cover 204 weakens the welding strength, so that the protective cover 220 could break off if used frequently.
It is therefore an object of the invention to provide a protective cover with ternary structure for solving the problems of losing the cover or forgetting to close. Also, the protective cover of the invention has a better mechanical strength and the lower cost.
According to the objective of the invention, the protective cover with ternary structure applied in an electronic product, wherein the electronic product has an expansion slot and a bottom cover, comprises a conjoint plate connected to the bottom cover, a flexible plate connected to the conjoint plate, and a fastening plate connected to the flexible plate. The fastening plate also snaps the bottom cover for covering the expansion slot. Additionally, the conjoint plate, the flexible plate, and the fastening plate are integrated as a whole by double injection technique, and the flexibility of the flexible plate controls the protective cover being closed or opened.